Pattern measurement device, and computer program

Abstract

A purpose of the present invention is to provide a pattern measurement device that allows the selection of device conditions for calculating proper variability and allows the estimation of proper variability. The present invention provides a pattern measurement device comprising a computation processing device that, on the basis of a plurality of measured values acquired by a charged particle radiation device, calculates the variability of the measured values of a pattern that is the object of measurement, said pattern measurement device characterized in that a variability σmeasured of the plurality of measured values formed at different positions and σ2observed=σ2pattern/Np+σ2sem0/(Np·Nframe) are used to calculate σSEM0, which indicates measurement reproducibility error. σpattern0 is the variability due to pattern shape error, Np is the number of measurement points, and Nframe is a value that changes according to device conditions.

The invention claimed is: 
     
       1. A pattern measurement device including a computation processing device that, on a basis of a plurality of measured values acquired by a charged particle radiation device, calculates a variability of the measured values of a pattern that is an object of measurement, the pattern measurement device comprising:
 a storage medium that stores the measured values of a pattern, wherein 
 the computation processing device is configured to calculate, using a variability σ measured  of the plurality of measured values formed at different positions, and an following expression including following parameters, σ SEM0  which indicates a measurement reproducibility error:
   σ 2   observed −σ 2   pattern0   /Np+σ   2   sem0 /( Np·N frame)  [Expression]
 
 
 
       [Parameters]
 σ pattern0 : a variability due to a pattern shape error 
 Np: a number of measurement points 
 Nframe: a value that changes according to device conditions. 
 
     
     
       2. The pattern measurement device according to  claim 1 , wherein
 the Nframe is a number of frames of the charged particle radiation device. 
 
     
     
       3. The pattern measurement device according to  claim 2 , wherein
 the computation processing device calculates the Nframe with which σ 2   pattern0 /Np+σ 2   sem0 /(Np·Nframe) satisfies a predetermined condition. 
 
     
     
       4. The pattern measurement device according to  claim 1 , wherein
 the computation processing device calculates a variability σ 2   CDpatterno  based on a following expression having following parameters:
   σ 2   CDpattern0   ·Np·σ   2   CDobserved −σ 2   CDsem0   /N frame  [Expression]
 
 
 
     
     
       5. The pattern measurement device according to  claim 1 , wherein
 the plurality of measured values are values measured at different timings and different positions. 
 
     
     
       6. A storage medium that stores a computer program which is readable by a computer and which enables the computer to calculate, on a basis of a plurality of measured values acquired by a charged particle radiation device, a variability of the measured values of a pattern that is an object of measurement, wherein
 the computer program causes the computer to calculate, using a variability σ measured  of the plurality of measured values formed at different positions, and a following expression including following parameters, σ SEM0  which indicates a measurement reproducibility error:
   σ 2   observed =σ 2   pattern0   /Np+σ   2   sem0 /( Np·N frame)  [Expression]
 
 
 
       [Parameters]
 σ pattern0 : a variability due to a pattern shape error 
 Np: a number of measurement points 
 Nframe: a value that changes according to device parameters.